CN1290962C - Nano polishing liquid for high dielectric material strontium barium titanate chemical-mechanical polish - Google Patents

Abstract

The invention relates to a nano-polishing liquid used for chemical mechanical polishing (CMP) of barium strontium titanate ( _{BaxSr1 -xTiO3 ,} BST), a high-permittivity dielectric material in semiconductor devices. The CMP nano-polishing fluid contains nano-abrasives, chelating agents, pH regulators, surfactants, defoamers, bactericides and solvents. The polishing liquid has less damage, is easy to clean, does not corrode equipment, and does not pollute the environment. It is mainly used for the dielectric material of a new generation of high-density memory (DRAM) capacitors and the gate dielectric of CMOS field effect transistors—high dielectric constant dielectric material titanium Global planarization of barium strontium oxide. Using the above-mentioned nano-polishing liquid to planarize the high-permittivity dielectric material barium strontium titanate by chemical mechanical polishing, the surface roughness after polishing is reduced to below 0.8nm, and the polishing rate reaches 200-300nm/min; the surface is globally flat after polishing It has high precision and less damage. It is an efficient polishing solution for planarizing high dielectric materials when preparing ultra-high density dynamic memory (DRAM) and CMOS field effect transistors.

Description

Nano-polishing liquid for chemical-mechanical polishing of strontium barium titanate

technical field

The invention relates to a nanometer polishing fluid for chemical mechanical polishing (CMP) and its application in chemical mechanical polishing of high dielectric constant materials in next-generation semiconductor devices. More precisely, it is used in the next generation of semiconductor devices (ultra-high-density dynamic memory (DRAM) and nano-sized CMOS field-effect transistors), and the application of nano-polishing fluid and device preparation process for chemical-mechanical polishing of high-permittivity dielectric materials barium strontium titanate , The invention belongs to the technical field of microelectronic auxiliary materials and integrated circuit processing technology.

Background technique

Memory and logic devices are the most important components of semiconductor devices, and dielectric materials are at the core of these two devices; it can be used as a dielectric material for dynamic random access memory (DRAM) capacitors to store information, and as a The gate dielectric of CMOS field effect transistor logic devices. With the rapid development of integrated circuits in accordance with Moore's Law, the feature size of devices has shrunk to 90 nanometers, and 65nm and 45nm processes are under development. However, due to the small size effect, the processing technology has been developed close to the limit, so it is necessary to solve the existing factors that restrict the development by adopting new materials or proposing new device models. For ultra-high-density DRAM, it is required to store digital information in a smaller area, and then it is required to maintain the value of its capacitance when the area of the capacitor is reduced. When the thickness of the capacitor dielectric is constant, the only way to maintain the same capacitance and reduce the capacitor area is to increase the dielectric constant of the capacitor filled medium, that is, to use a high dielectric constant dielectric material. For the gate dielectric of field effect transistors, SiO ₂ dielectric is generally used. However, with the nanometerization of the device size, in order to suppress the short channel effect and ensure that the device has good device characteristics, the required gate dielectric layer is getting thinner and thinner. At this time, many secondary effects are caused, such as: direct tunneling of electrons Effect; the leakage current caused by the sharp increase of the gate electric field of the gate dielectric layer deteriorates the original basic device characteristics, and even fails to work normally. For this reason, field effect transistors with smaller dimensions must use high dielectric constant materials as the gate dielectric to replace the traditional SiO ₂ , so as to ensure that the physical thickness of the dielectric layer is increased under the condition of constant equivalent thickness, so as to reduce the direct tunneling effect and the electric field strength of the gate dielectric layer. Barium strontium titanate (BST) thin film is a high-quality high-dielectric material. By selecting the Ba/Sr ratio reasonably, the material can be in the paraelectric phase at room temperature and application temperature, avoiding the fatigue phenomenon caused by the ferroelectric domain switching effect; it It also has relatively low dielectric loss, small leakage current, and high dielectric constant, which just meet the requirements of the next generation of semiconductor devices for dielectric materials. BST has been considered to be used in the development of next generation semiconductor devices , such as the important dielectric material of ultra-high density DRAM and nanometer-sized CMOS field effect transistors, ITRS predicts that BST will be the first choice for high-K materials in the 65-nanometer process in 2007. With the nanometerization of the feature size of the device, the lithography exposure resolution of the IC process is required to be higher and higher. The resolution can be improved by using a shorter wavelength and larger numerical aperture exposure system, but at the same time it leads to the problem of shallow depth of focus. This requires a high degree of planarization of the exposed surface, and the only technology to achieve global planarization of the wafer surface is chemical mechanical polishing (CMP), especially for IC processes with feature sizes smaller than 0.25 microns, CMP has become a key process One of the techniques. Combined with the development needs of BST in the next generation of semiconductor devices and the high planarization of the wafer surface required by the nano-sized IC manufacturing process, the CMP research on BST is becoming increasingly important and has become a bottleneck for the development of the next generation of semiconductor devices. Check domestic and foreign patents and documents, so far there are few reports about BST thin film CMP, US5695384 discloses a kind of salt polishing solution for BST workpiece CMP, contains 85wt% water in the polishing solution provided by this invention patent, 4wt% NaCl, 4wt% H ₂ O ₂ and 7wt% colloidal silica, the polishing rate is about 35nm/min. Because the polishing solution contains a large amount of Na ⁺ , it is extremely harmful to the process of semiconductor devices, and the polishing rate is too low to meet the industrial needs. Yong-Jin Seo et al. reported the CMP of BST films prepared by sol-gel technology. In the article, the author studied the performance of TiO ₂ as an abrasive polishing fluid. The polishing rate can reach 320nm/min, but the surface roughness is as high as 1.50 nm (Chemical mechanical polishing of Ba _0.6 Sr _0.4 TiO ₃ film prepared by sol-gel method, Microelectronic Engineering 75 (2004) 149-154). For the development needs of current devices and the higher requirements of next-generation devices, the surface roughness of the wafer is required to be less than 1.0nm, or even smaller. For the CMP of high-K material BST of ultra-high-density DRAM and nano-sized CMOS field effect transistors, a nano-polishing liquid is still needed to achieve high efficiency (polishing rate meets industrial needs), high flatness (surface roughness is less than 1.0nm), Low defect polished surface.

Contents of the invention

Based on the rapid development of current semiconductor devices (DRAM and nanometer size CMOS field effect transistors) and the continuous reduction of feature size, and the higher and higher requirements for high dielectric material surface flatness, the present invention is aimed at next generation semiconductor devices (DRAM and nanometer size CMOS field effect transistor) key material - high K (dielectric constant) dielectric material BST to carry out CMP research, provide BST-CMP nano-polishing liquid and use the polishing liquid to perform chemical mechanical polishing on BST, for the next generation of high-performance , high-density, high-reliability semiconductor device development to provide protection.

For DRAM, in order to achieve ultra-high density storage, high-K dielectric materials and smaller feature size processes must be used; for transistors, with the nanometerization of feature sizes, in order to suppress the short channel effect and ensure good device performance The device characteristics of the gate dielectric layer are getting thinner and thinner, causing many secondary effects, such as: the direct tunneling effect of electrons, the leakage current caused by the sharp increase of the gate electric field of the gate dielectric layer, which deteriorates the original basic device characteristics, for This smaller-sized field effect transistor must use a high dielectric constant material as the gate dielectric to replace the traditional SiO ₂ , so as to ensure that the physical thickness of the dielectric layer is increased under the condition of the same equivalent thickness to reduce direct tunneling effect and the electric field strength of the gate dielectric layer. With the feature size of next-generation semiconductor devices getting smaller and smaller, the lithography resolution requirements are getting higher and higher. The improvement of high resolution has caused the problem of shallow depth of focus, which puts forward higher requirements for the flatness of the material surface. . The high-K material BST is an important dielectric material in next-generation semiconductor devices, and the importance of its planarization research is similar to the CMP of Cu interconnects in deep submicron IC processes. But so far, there is little research on the CMP of the high-K material BST. The present invention provides a nano-polishing liquid of the high-K material BST-CMP, and uses the polishing liquid to CMP the high-K material BST thin film.

The chemical mechanical polishing nano-polishing liquid involved in the present invention contains nano-abrasives, oxidants, chelating agents, surfactants, polishing accelerators, defoamers, bactericides, pH regulators and solvents.

The CMP nano-polishing liquid provided by the present invention includes at least one oxidizing agent. The oxidizing agent helps to oxidize the thin film material to the corresponding oxide, hydroxide or ion. The oxidizing agent can be selected from compounds that form hydroxyl groups during reduction or high-valent ion compounds that can reduce their valence, such as any one or both of hydrogen peroxide, urea hydrogen peroxide, and ammonium persulfate. Among them, urea hydrogen peroxide, ammonium persulfate or their mixtures are preferred as the oxidizing agent.

The content of oxidant in the nano-polishing liquid provided by the invention can be 0.5wt% to 15.0wt%; the preferred oxidant content is 0.5wt% to 10.0wt%; the optimum oxidant content is 1.0wt% to 7.0wt%. If urea hydrogen peroxide is used as an oxidizing agent, the molar ratio of urea to hydrogen peroxide ranges from 0.50:1 to 2:1. If 33.5wt% hydrogen peroxide and 66.5wt% urea are contained in the urea hydrogen peroxide, the optimum content of urea hydrogen peroxide is correspondingly 3.0wt% to 21.0wt%.

The CMP nano-polishing liquid provided by the invention includes at least one chelating agent. The role of the chelating agent is to form a chelate with the metal ions on the polishing surface and a small amount of metal ions in the polishing solution, which helps to reduce the pollution of the metal ions on the polishing surface and increase the volume of the polishing product, making it easy to remove after polishing. The chelating agent can be selected from metal ion-free chelating agents, such as any one of ammonium ethylenediaminetetraacetate, ammonium citrate, and hydroxyethylammonium ethylenediaminetetraacetate or any two mixtures thereof. One of ammonium citrate, ammonium hydroxyethylethylenediaminetetraacetate or a mixture thereof is preferred.

The content of the chelating agent in the nano-polishing liquid can be 0.1wt% to 10.0wt%; the preferred content of the chelating agent is 0.1wt% to 5.0wt%; the optimum content of the chelating agent is 0.3wt% to 3.0wt%.

The CMP nano-polishing liquid provided by the present invention includes at least one metal oxide nano-abrasive material. The main function of the abrasive is mechanical friction during CMP, which can be selected from aluminum oxide, titanium oxide, colloidal silicon oxide and mixtures thereof. The abrasive is preferably titanium oxide, colloidal silicon dioxide and mixtures thereof.

The average particle diameter of the grinding material used in the present invention is less than 200 nanometers, and the optimum average particle diameter is 10-120 nanometers. The grinding material is an aqueous dispersion of metal oxides or a colloidal solution of metal oxides.

The abrasive content in the CMP nano-polishing liquid can be 1.0wt% to 30.0wt%; the preferred abrasive content is 1.0wt% to 20.0wt%; the optimum abrasive content is 2.0wt% to 15.0wt%.

The CMP nano-polishing liquid provided by the present invention includes at least one surfactant. The role of the surfactant mainly includes high stability of the dispersion of the abrasive in the polishing liquid; during the CMP process, it is preferentially adsorbed on the surface of the material surface, and the chemical corrosion is reduced. Because the friction force of the concave part is small, the convex part is more polished than the concave part. The high speed improves the polishing selectivity; the surfactant also helps to clean the surface pollutants after polishing. Surfactants used in the present invention can be nonionic surfactants, cationic surfactants, anionic surfactants; can be selected from metal ion-free alkyl alcohol polyoxyethylene ethers, alkyltrimethylammonium bromide , ammonium polyacrylate, ammonium polymethacrylate, any one or both; preferably alkyl alcohol polyoxyethylene ether, ammonium polyacrylate, ammonium polymethacrylate and mixtures thereof.

The surfactant content in the CMP nano-polishing liquid is 0.01wt% to 2.0wt%; the preferred surfactant content is 0.01wt% to 1.0wt%; the optimum surfactant content is 0.01wt% to 0.5wt%.

The CMP nano-polishing liquid provided by the invention includes at least one polishing accelerator. Considering the removal of BST film materials after chemical reactions, the corresponding oxides such as BaO, SrO, TiO ₂ are formed through the treatment of oxidants, and the corresponding hydroxides are formed under the action of alkaline solution, but these types of hydroxides are all It is a slightly soluble or even insoluble substance in water, which is easy to deposit on the polishing surface to form particle sticky dirt and affect further material removal. In the present invention, a metal ion-free halide is added as an accelerator to form a water-soluble halide with the above-mentioned hydroxide, which enhances the removal of the surface film and accelerates the polishing rate; inhibits the formation of surface particles and reduces scratches and roughness. The polishing accelerator used in the present invention is selected from halides without metal ions, such as any one or two of ammonium fluoride, ammonium chloride and ammonium bromide; ammonium fluoride, ammonium chloride and mixtures thereof.

The polishing accelerator content in the CMP nano-polishing liquid is 0.5wt% to 5.0wt%; the preferred surfactant content is 0.5wt% to 4.0wt%; the optimum surfactant content is 0.8wt% to 2.0wt%.

The CMP nano-polishing liquid provided by the present invention includes a defoaming agent. The addition of surfactants in the polishing liquid usually leads to the generation of foam, which is not conducive to process production control. Low-foaming or no-foaming polishing can be achieved by adding a very small amount of defoaming agent. Liquid, easy to operate and use. The defoamer in the present invention is selected from polysilane compounds, such as polydimethylsilane.

The defoamer content in the CMP nano-polishing liquid can be 20-200ppm; the preferred defoamer content is 40-150ppm; the optimum defoamer content is 40-120ppm.

The CMP nano-polishing liquid provided by the present invention includes a bactericide. The polishing liquid contains a lot of organic matter. Long-term storage is easy to form mold and cause the polishing liquid to deteriorate. For this reason, a small amount of bactericide is added to the polishing liquid to achieve this purpose. The bactericide described in the present invention is selected from thiazolinone compounds, such as isomeric thiazolinones.

The bactericide content in the CMP nano-polishing liquid can be 10 to 50 ppm; the preferred defoamer content is 10 to 30 ppm; the optimum defoamer content is 10 to 20 ppm.

The CMP nano-polishing solution provided by the present invention includes at least one pH regulator. The pH regulator is mainly to adjust the pH value of the polishing liquid, so as to make the polishing liquid stable and help the CMP to proceed. The pH regulator used in the present invention can be selected from any one or two mixtures of ammonia, potassium hydroxide, tetramethylammonium hydroxide, hydroxylamine; preferably no metal ion compounds, such as ammonia, tetramethylammonium hydroxide Ammonium, hydroxylamine, and mixtures of any two thereof.

The pH value of the nano-polishing solution is 7-12, preferably 8-11.5, and the optimum pH value is 8.5-11.

The solvent in the nano-polishing liquid provided by the invention is deionized water.

The nano-polishing liquid provided by the present invention can be used for high dielectric constant material CMP, especially for the preparation of high dielectric constant dielectric materials of ultra-high density DRAM and nano-sized CMOS field effect transistors, and described high dielectric constant material titanium The general formula of barium strontium acid is Ba _x Sr _1-x TiO ₃ , where 0<x<1.0.

The nano-polishing solution provided by the present invention can be applied to the chemical mechanical polishing of the high dielectric constant material strontium barium titanate: using magnetron sputtering or sol-gel film forming technology to deposit high dielectric constant media on silicon substrates Layer BST thin film (see embodiment 8 for details), its polishing rate reaches 200～300nm/min, is suitable with the literature report value, but after polishing, the surface roughness drops below 0.8nm, so it is a kind of ideal chemical mechanical polishing liquid .

The above-mentioned high-K dielectric material BST is difficult to achieve better etching for the current IC etching process conditions, and there are few related chemical mechanical polishing studies. By using the nano-polishing solution provided by the present invention, the high-K dielectric material BST film can be realized The global planarization of the surface, the roughness RMS of the polished surface is less than 0.8nm, which meets the high planarization requirements for the preparation of high-performance and small-sized semiconductor devices.

Detailed ways

Further illustrate substantive characteristics and remarkable progress of the present invention by following examples. However, the present invention is by no means limited to the Examples.

【Example 1】

Preparation of nano-polishing liquid: the polishing liquid contains 20wt% of silica colloid of 10-30 nanometers, 12.0wt% of urea hydrogen peroxide; 0.3wt% of ammonium hydroxyethyl ethylenediamine tetraacetate; Oxyethylene ether 0.2wt%; ammonium chloride 1.0wt%, polydimethylsilane 50ppm, isomeric thiazolinone 10ppm, tetramethylammonium hydroxide as pH regulator, pH value is 10.8, the rest is deionized water .

【Example 2】

Preparation of nano-polishing liquid: the polishing liquid contains 5wt% of silica colloid of 10-30 nanometers, 4wt% of titanium dioxide of 40 nanometers, 10.0wt% of urea hydrogen peroxide; 0.5wt% of ammonium citrate; 0.3wt% of ammonium polyacrylate , dodecyl alcohol polyoxyethylene ether 0.1wt%; ammonium chloride 1.5wt%, polydimethylsilane 50ppm, isomeric thiazolinone 10ppm, hydroxylamine is the pH regulator, the pH value is 9.8, and the rest are ionized water.

[Embodiments 3-7] Example Abrasives oxidizing agent Chelating agent Accelerator Surfactant pH regulator other 3 SiO ₂ , 10-30nm, 5wt%; TiO ₂ , 120nm, 2wt% Ammonium persulfate 3.0wt% Ammonium citrate 2.0wt% Ammonium chloride 1.2wt% Ammonium polymethacrylate 0.2wt% Ammonia, hydroxylamine, pH9.2 Deionized water 4 SiO ₂ , 10-30nm, 5wt%; Al ₂ O ₃ , 80nm, 2wt% _{H2O2 1.0wt} %, urea hydrogen peroxide 5.0wt% Ammonium Hydroxyethylethylenediaminetetraacetate 1.0wt% Amine fluoride 0.8wt% Lauryl alcohol polyoxyethylene ether 0.3wt% Tetramethylammonium hydroxide pH9.8 Deionized water 5 Al ₂ O ₃ , 80nm, 5wt% Ammonium persulfate 4.0wt% Ammonium citrate 3.0wt% Ammonium Fluoride 1.1wt% Ammonium dodecylsulfonate 0.5wt% Ammonia, hydroxylamine pH10.2 Deionized water 6 SiO ₂ , 10-30nm, 5wt%; TiO ₂ , 120nm, 2wt% _{H2O2 2.0wt} %, ammonium persulfate 1.0wt% Ammonium hydroxyethylethylenediaminetetraacetate 0.5wt% Ammonium chloride 2.0wt% Ammonium polyacrylate 0.1wt%, lauryl alcohol polyoxyethylene ether 0.1wt% Ammonia, hydroxylamine pH10.2 Deionized water 7 SiO ₂ , 10-30nm, 5wt%; Al ₂ O ₃ , 80nm, 2wt% Urea hydrogen peroxide, 7.0 wt% Ammonium hydroxyethylethylenediaminetetraacetate 0.5wt% Ammonium chloride 0.8wt% Ammonium polymethacrylate 0.1wt%, lauryl alcohol polyoxyethylene ether 0.1wt% Ammonia, hydroxylamine pH10.2 Deionized water

Note: The average particle size of the abrasive is preferably 10-120 nanometers; the defoamer is polydimethylsilane, and the addition amount is 50ppm; the fungicide is isothiazolinone, and the addition amount is 10ppm.

【Embodiment 8】

CMP test: the CP-4 polishing machine of CETR Company of the United States is adopted, the polishing pad is IC 1000/SubaIV, the polishing machine chassis speed is 100rpm, the polishing head speed is 97rpm, the polishing liquid flow rate is 200ml/min, and the pressure is 3psi. Compositions provided in Embodiment 7, the polishing pad sample is Si/BST. The RMS roughness of the polished surface was measured by an atomic force microscope (AFM), and the results are shown in Table 2. As can be seen from the table, the nano-polishing solution provided by the present invention carries out BST-CMP, and the polishing rate can reach 200-300nm/min, and the surface roughness RMS after polishing has dropped below 0.8nm, which can meet the flatness of high-performance semiconductor devices. requirements.

Table 2 Polishing test results Polishing fluid BST polishing rate (A/min) Roughness RMS(nm) Polishing fluid 1 2180 0.77 Polishing fluid 2 3240 0.65 Polishing fluid 3 2630 0.68 Polishing fluid 4 2810 0.80 Polishing fluid 5 3020 0.72 Polishing fluid 6 3640 0.61 Polishing fluid 7 2040 0.80

Claims (7)

1, a kind of nanometer burnishing liquid that is used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical is characterized in that nanometer burnishing liquid contains:

1. one or both oxygenants, its content is 0.5～15.0wt%; Described oxygenant is selected from hydrogen peroxide, Urea Peroxide or the ammonium persulphate any one or wherein any two kinds of mixtures;

2. at least a sequestrant, its content are 0.1～10.0wt%; Described sequestrant is selected from ethylenediamine tetraacetic acid (EDTA) ammonium, ammonium citrate or the hydroxyethylethylene diamine tetraacethyl ammonium any one or wherein any two kinds of mixtures;

3. one or both metal oxide nano abrasives, its content is 1.0～30.0wt%; Described nano-abrasive is selected from aluminum oxide, titanium oxide or colloidal silica any one or any two kinds of mixtures, and the median size of nano-abrasive is less than 200 nanometers;

4. one or both tensio-active agents, its content is 0.01～2.0wt%; Described tensio-active agent is selected from a kind of or any two kinds of mixtures in alkyl alcohol polyoxyethylene groups ether, alkyl trimethyl ammonium bromide or the anion pp hydrochlorate of non-metallic ion;

5. one or both polish promotor, and its content is 0.5～5.0wt%; Described polishing promotor is selected from a kind of or any two kinds of mixtures in Neutral ammonium fluoride, ammonium chloride and the brometo de amonio;

6. a kind of defoamer, its content are 20～200ppm; Described defoamer is selected from polydimethyl silane;

7. a kind of sterilant, its content are 10～50ppm; Described sterilant is selected from the isomery thiazolinone;

8. to regulate the pH scope be 7～12 in the pH regulator agent, and described pH regulator agent is selected from any one or any two kinds of mixtures in ammoniacal liquor, potassium hydroxide, Tetramethylammonium hydroxide or the oxyamine;

9. surplus is a deionized water as solvent in the polishing fluid.

2, the described nanometer burnishing liquid that is used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical of claim 1 is characterized in that:

1. described oxygenant is selected from ammonium persulphate, Urea Peroxide or both mixtures;

2. described sequestrant is selected from a kind of in ammonium citrate, the hydroxyethylethylene diamine tetraacethyl ammonium or their mixture;

3. described nano-abrasive median size 10～120 nanometers are selected from aluminum oxide, titanium oxide, colloidal silica or their mixture;

4. described tensio-active agent is selected from alkyl alcohol polyoxyethylene groups ether, ammonium polyacrylate or its mixture of non-metallic ion;

5. described polishing promotor is selected from a kind of or its mixture in the Neutral ammonium fluoride of non-metallic ion or the ammonium chloride;

6. described pH regulator agent is selected from ammoniacal liquor, Tetramethylammonium hydroxide or the oxyamine any one or its any two kinds of mixtures.

3, according to claim 1 or the 2 described nanometer burnishing liquids that are used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical, it is characterized in that:

1. oxygenate content is 0.5～10.0wt%;

2. sequestrant content is 0.1～5.0wt%;

3. nano-abrasive content is 1.0～20.0wt%;

4. polishing accelerator content is 0.5～4.0wt%;

5. antifoam content is 40～150ppm;

6. sterilant content is 10～30ppm;

7. surfactant content is 0.01～1.0wt%;

8. the pH value is 8～11.5.

4, according to claim 1 or the 2 described nanometer burnishing liquids that are used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical, it is characterized in that:

1. oxygenate content is 1.0～7.0wt%;

2. sequestrant content is 0.3～3.0wt%;

3. nano-abrasive content is 2.0～15.0wt%;

4. polishing accelerator content is 0.8～2.0wt%;

5. antifoam content is 40～120ppm;

6. sterilant content is 10～20ppm;

7. surfactant content is 0.01～0.5wt%;

8. the pH value is 8.5～11.

5, according to the described nanometer burnishing liquid that is used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical of claim 3, it is characterized in that:

1. oxygenate content is 1.0～7.0wt%;

2. sequestrant content is 0.3～3.0wt%;

3. nano-abrasive content is 2.0～15.0wt%;

4. polishing accelerator content is 0.8～2.0wt%;

5. antifoam content is 40～120ppm;

6. sterilant content is 10～20ppm;

7. surfactant content is 0.01～0.5wt%;

8. the pH value is 8.5～11.

6, according to claim 1 or the 2 described nanometer burnishing liquids that are used for the mechanical polishing of high dielectric constant material strontium barium titanate chemical, when it is characterized in that using the Urea Peroxide oxygenant, the mol ratio of urea and hydrogen peroxide is 0.5: 1～2.0: 1.

7, use according to the described chemically machinery polished that is used for the nanometer burnishing liquid of high dielectric constant material strontium barium titanate chemical machine polishing liquor in claim 1 or 2, it is characterized in that being used on silicon substrate, utilizing the Ba of magnetron sputtering or collosol and gel masking technique deposition high-k _xSr _1-xTiO ₃, 0＜x＜1.0 wherein, the chemically machinery polished of film, the roughness of surface of polished is reduced to below the 0.8nm, and polishing speed reaches 200～300nm/min.